We're aware of an issue with Facebook purchases for all King Games and our team is on it. ๐ ๏ธ Hang tight while we fix things! You can still enjoy the game, and we'll keep you posted once it's solved.
There will be more challange for this badge apperently. So you will get more attempts to go for this badge. Something like "beat the mod" I guess. Several contests a year, but once you got it, you got it.